The impact of cement slurry aging creep on the construction process of oil wells

•New viscoplastic model for salt creep motion including transient creep.•The solidification theory applied to the cement slurry.•Finite element construction model of pre-salt well drilled into Brazilian Halite.

In the present work, a finite element based methodology was developed to assess the deformations and stresses during the construction of a vertical oil well drilled into Brazilian Halite. The impact of each construction stage is addressed focusing on the investigation of the early age creep of the cement slurry and its effects on the well integrity. The cement slurry was considered as an aging viscoelastic material and a parametric case study was addressed using the solidification theory. The rock salt constitutive model accounted for the primary and secondary creep through a combination of a power law and the double mechanism law. It was observed that if the cement slurry time-dependent behavior is neglected, the development of deviatoric stresses in cement slurry and hazard phenomena may be overlooked.